The gastrointestinal tract not only is involved in digestion and absorption, but also interacts with the immune system to promote good health. The inside of the intestinal tract is coated with a thin layer of sticky, viscous mucous, and embedded in this mucus layer, are millions and millions of bacteria and other microbes. When the intestinal bacteria are in balance (i.e., the good bacteria outnumber the bad bacteria), the gut is said to be healthy. Intestinal problems arise, however, when the levels of pathogenic bacteria increase or when bacteria that normally populate the lower intestinal tract are relocated to the upper intestinal tract. Because of the relationship between good gut health and the overall health and well being of the organism, means for promoting or improving gut health are needed. For example, there is a need for methods for improving gut health by improving the digestibility of dietary proteins and/or decreasing the levels of bacteria comprising Clostridium in the upper intestinal tract of an organism.